- Mar 7, 2013
- 29
Greeting. I've been a member for a few years now, and the info/advise here is invaluable. This is my first post and I could really use some help. I'm having an overheating issue that I cannot track down. Any help would be a tremendous help.
My daily drive is a 2003 TB (4.2, 4x4, 261k miles), and I commute 64 miles on the highway each way every day and never had an issue with it that I couldn't find the answer to here on the forum (thanks for all the info) until now.
A little over a month ago my air went out. The compressor had given out and I sent it to a local shop to have this fixed. Here in Georgia the summers can be brutal (96-102 degrees daily) so I didn't hesitate to have the AC repaired, worth every penny. The day after I got the TB out of the shop I headed to Atlanta for work. I made it half way before I got the "check gauges" light. I was starting to over heat. The needle was just past the the 3/4 mark. I pulled off and popped the hood to find that the water had migrated into the reservoir. Left the hood popped to cool as I waited for the tow truck. Once I got it home I took a look and found that the radiator cap had broken in two pieces. Replaced it and went on my way. Started to over heat again. The temp stays normal (to the left side of 210) as long as I'm driving around town, even with the air on, however once I hit the highway it will tick up to 2 marks above normal after about 10-20 minutes. Service engine soon is not on.
Two years ago I:
- replaced the fan clutch (Dorman...clicking piece of crap)
- replaced the radiator (broken upper hose connector)
- replaced the water pump
- replaced upper and lower radiator hoses
Trying to track the current problem down I have:
- changed the thermostat
- changed the fan clutch (OEM AC Delco)
- cleaned the radiator (small blockage in the center)
- flushed the engine and radiator
- had the fan clutch software updated (GM stealership...$109 to plug up a computer and hit buttons)
- cleaned throttle body
- replaced oil sending unit (lost oil pressure at idle, problem hasn't returned)
- checked the temp gauge against my scan tool and it's dead on.
I got it back from the radiator shop yesterday and test drove it down the highway today to check for progress. Still moves up 2 marks. But I did notice that it feels like it had no acceleration. The transmission would hit passing gear just to speed up, and my gas mileage is down from 19.9mpg on highway to 15.1 mpg. I have also ruled out the head gasket as I have no water in my oil or oil in my water.
My line of thought is starting to lead to towards maybe a clogged or clogging catalytic converter causing excessive heat in the engine. if this isn't the issue then I am at a loss and have no idea where to go next. It's starting to make me question all that I thought I know about engines.
I love my TB and have always planned to drive it until the wheels fall off, and I refuse to let a few exrta degrees be the death of her. Any help or advise would be greatly appreciated.
My daily drive is a 2003 TB (4.2, 4x4, 261k miles), and I commute 64 miles on the highway each way every day and never had an issue with it that I couldn't find the answer to here on the forum (thanks for all the info) until now.
A little over a month ago my air went out. The compressor had given out and I sent it to a local shop to have this fixed. Here in Georgia the summers can be brutal (96-102 degrees daily) so I didn't hesitate to have the AC repaired, worth every penny. The day after I got the TB out of the shop I headed to Atlanta for work. I made it half way before I got the "check gauges" light. I was starting to over heat. The needle was just past the the 3/4 mark. I pulled off and popped the hood to find that the water had migrated into the reservoir. Left the hood popped to cool as I waited for the tow truck. Once I got it home I took a look and found that the radiator cap had broken in two pieces. Replaced it and went on my way. Started to over heat again. The temp stays normal (to the left side of 210) as long as I'm driving around town, even with the air on, however once I hit the highway it will tick up to 2 marks above normal after about 10-20 minutes. Service engine soon is not on.
Two years ago I:
- replaced the fan clutch (Dorman...clicking piece of crap)
- replaced the radiator (broken upper hose connector)
- replaced the water pump
- replaced upper and lower radiator hoses
Trying to track the current problem down I have:
- changed the thermostat
- changed the fan clutch (OEM AC Delco)
- cleaned the radiator (small blockage in the center)
- flushed the engine and radiator
- had the fan clutch software updated (GM stealership...$109 to plug up a computer and hit buttons)
- cleaned throttle body
- replaced oil sending unit (lost oil pressure at idle, problem hasn't returned)
- checked the temp gauge against my scan tool and it's dead on.
I got it back from the radiator shop yesterday and test drove it down the highway today to check for progress. Still moves up 2 marks. But I did notice that it feels like it had no acceleration. The transmission would hit passing gear just to speed up, and my gas mileage is down from 19.9mpg on highway to 15.1 mpg. I have also ruled out the head gasket as I have no water in my oil or oil in my water.
My line of thought is starting to lead to towards maybe a clogged or clogging catalytic converter causing excessive heat in the engine. if this isn't the issue then I am at a loss and have no idea where to go next. It's starting to make me question all that I thought I know about engines.
I love my TB and have always planned to drive it until the wheels fall off, and I refuse to let a few exrta degrees be the death of her. Any help or advise would be greatly appreciated.
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